ACCIDENTS AND LESIONS
METHOD / HOW IT WORKS / ADVANTAGES / DISADVANTAGES
ACCIDENTS
(Phineas Gage) /
- Examine an individual’s behavior after experiencing damage to a specific part of the brain due to an accident
- Allows for educated guesses about links between brain structure and function
- Allows research on fluke circumstances that are impossible/unethical to recreate in lab
- Little or no experimental control
- Issues associated with case studies (see Research Data and Methods chart)
LESIONS
(removal, destruction of part of brain) /
- Examine an individual’s behavior after suffering brain damage due to disease, psychosurgery, genetic factors, etc.
- Allows for educated guesses about links between brain structure and function
- Allows research on fluke circumstances that are impossible/unethical to recreate in lab
- Little or no experimental control
- Issues associated with case studies (see Research Data and Methods chart)
EEG & NEUROIMAGING TECHNIQUES
METHOD / HOW IT WORKS / ADVANTAGES / DISADVANTAGES
ELECTROENCEPHOGRAM (EEG) /
- Amplified recording of brain’s electrical activity (“brainwaves”) via electrodes placed on scalp
- High temporal resolution
- Non-invasive, painless procedure
- Low spatial resolution
COMPUTERIZED
AXIAL TOMOGRAPHY
(CAT, CT) scan /
- X-ray cameras rotate around head, combining images into 3D picture of brain structure
- High resolution images of brain structure
- Allows direct view of level of interest
- Potential damage due to high radiation levels
- No information about brain function
POSITRON EMISSION TOMOGRAPHY
(PET) scan /
- Tracks brain’s consumption of radioactive glucose injection, providing images of brain function
- Allows researchers to examine which brain areas consume most energy in a given task, thus providing information about brain function
- Radiation injection
- Lengthy process
- Expensive equipment needed to create radioactive isotopes
- No information about brain structure
MAGNETIC RESONANCE IMAGING
(MRI) /
- Strong magnetic field causes disorientation of atoms in brain; reorientation=signal as to soft tissue density (picture of brain structure)
- Allows researchers to examine brain structure without exposure to radiation involved in CT scan
- Non-invasive, painless procedure
- Can be an uncomfortable, claustrophobic experience
- No information about brain function
FUNCTIONAL MAGNETIC RESONANCE IMAGING (FMRI) /
- Type of MRI that detects amount of blood flow in different brain regions (proxy for oxygen consumption; brain function)
- High spatial resolution (3-6 millimeters)
- Non-invasive, painless procedure
- Quick imaging process
- Can be uncomfortable, claustrophobic experience